1. Field of the Invention
The present invention relates to particle powder synthesis. More specifically, the present invention discloses a method of utilizing sol-gel processing, flame synthesis and non-vacuum physical evaporation to produce high quality fine or ultra fine particle powder.
2. Description of the Prior Art
Traditional approaches of sol-gel processing to produce fine powder particles usually requires the mixed solution containing both precursor and organic solvent be placed in an oven and slowly heated to a temperature slightly higher than the flash point, but lower than the boiling point, of the solvent.
However, the solvent may take more than a month to be completely vaporized. Furthermore, even after such vaporization, only the precursor is obtained, and fine powder particles have not been produced yet. Moreover, a large portion of the precursor along with the solvent will be vaporized during such a long process.
As a heating source is a requisite to such a process, the energy cost is significant. Also, because the processing time is incredibly long, not only the productivity remains low, but also the precursor will clot and cause the grains to grow larger. Thus, the particle quality is poor. Because solvent vaporization is also a requisite to such a process, other disadvantages of such process include low productivity, contamination, air pollution, etc.
Other approaches to produce fine particle powder include solvent vaporization, freeze drying, spray drying, thermal spraying, precipitation, hydro flame drying, etc. However, all of these approaches require higher energy costs, cause air pollution, and still have barriers to produce fine particles of extremely small dimensions.
Therefore, there is a need for a low cost and efficient method of producing high quality fine or ultra fine particle powder.